1. Field of the Invention
The present invention relates to a semiconductor device, used for aging device, and more particularly to a semiconductor device applied in a Solid-State Aging Devices (SSAD), and an operation method and an application circuit thereof.
2. Description of Related Art
An electronic timer being free from a battery has been expected in various applications. Usually, the SSAD unit that includes a circuit for controlling expiration has been proposed as the integrated circuit of a battery-less electronic timer (IBLET). The fundamental idea of controlling expiration is to suppress the error in timing caused by anomalous charge loss, as shown in FIGS. 1-4. FIGS. 1-4 are schematically drawing, illustrating the conventional timer mechanism. In FIGS. 1-4, three time cells (A), (B), and (C) are used to exemplify the above concept. The lifetimes (time to switch-off) of the three cells (A), (B), and (C) are respectively short, middle, and long. Further, these three time cells (A), (B), and (C) are electronically connected in parallel between two terminals, indicated as terminal-1 and terminal-2. The currents through these time cells become zero in sequence of the lifetime of the time cells.
In the initial state, as shown in FIG. 1, the currents flow through all the time cells between the terminals. As the time cell with the shortest lifetime (A) among the three time cells expires firstly progressively with time, the currents through the shortest lifetime (A) become zero, while the currents flow through the remaining time cells with the middle lifetime (B) and with the long lifetime (C), as shown in FIG. 2. As time elapse further, the time cells expire in sequence; and gradually, the currents flow through only the time cell with the longest lifetime (C), as shown in FIG. 3. When the lifetime of the time cell with the longest lifetime (C) expires, the currents through the terminal-1 and terminal-2 reduce to zero, which implies that the electronically connection between the terminal-1 and terminal-2 is terminated, as shown in FIG. 4. Accordingly, a state of electrical electronically connection between the terminals is determined by the time cell with the longest lifetime (C) among the parallel-electronically connected time cells between the terminal-1 and terminal-2.
The time cell can be fabricated by a SSAD structure. However, the aging property of the SSAD structure may be changed due to physical manipulation on the SSAD, such as temperature or the other factors. The physical manipulation usually causes an error of result.
Nothing, however, herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms a part of the common general knowledge in the art.